Compound Feature Generation in Classification of Error Rate of Data Retrieved from Memory Cells

2. The device of claim 1, wherein each respective region in the plurality of separate regions of voltage includes a read voltage applied to the memory cells in determination of the data retrievable from the memory cells.

3. The device of claim 2, configured to control an operation to read the memory cells based on a classification of the bit error rate determined based at least in part on the feature.

4. The device of claim 3, configured to decide, based on the classification, whether to re-calibrate voltages to read the memory cells.

7. The device of claim 6, wherein each of the plurality of separate regions of voltage includes a candidate for the read voltage and a respective set of signal and noise characteristics of the memory cells measured based on the candidate; and the circuit is configured to compute the read voltage based on the respective set of signal and noise characteristics of the memory cells measured based on the candidate.

9. The device of claim 8, wherein the circuit is configured to compute the first feature in parallel with measuring the further set of signal and noise characteristics of the memory cells.

10. The device of claim 7, wherein the circuit is configured to apply a plurality of test voltages, configured according to the candidate, to the memory cells; and for each respective test voltage among the plurality of test voltages, the circuit is configured to determine, for the respective set of signal and noise characteristics, a count of a subset of the memory cells having a predetermined state when applied the respective test voltage.

12. The method of claim 11, wherein each respective region in the plurality of separate regions of voltage includes a read voltage applied to the memory cells in determination of the data retrievable from the memory cells.

14. The method of claim 13, wherein the controlling includes deciding, based on the classification, whether to re-calibrate voltages to read the memory cells.

15. The method of claim 13, wherein the controlling includes selecting, based on the classification, a decoder from a plurality of decoders to decode the data retrieved from the memory cells using the read voltage in the respective region.